Brake pads DIY repair

In detail: do-it-yourself brake pads repair from a real master for the site my.housecope.com.

The natural answer to the question: "When do you need to repair the brake pads?" will be, of course - exactly at the moment when they fail. But, not everything is so simple, especially with the car's braking system. After all, independent restoration of pads in the conditions of your own garage, as a rule, is fraught with a huge danger to the car, its driver and passengers. In addition, brake system malfunctions are a blow to the car owner's pocket, since with faulty brake pads or brake discs, fuel consumption and wear of the caliper parts increase.

It is necessary to think about replacing or repairing brake pads as soon as their malfunction is detected.

If a car's brake pads are knocking, there may be various reasons for this: brake disc wear, loose springs, etc. The elimination of all these breakdowns occurs, depending on the results of diagnostics, and the owner of the car is able to fix some malfunctions with his own hands. Moreover, repair kits with a set of small parts are sold for repairing brake pads.

If, even new, brake pads whistle, then again there are several reasons for this. Lapping pads, brake disc malfunctions or a small area of contact with the disc of an unevenly worn pad.

The very concept of "repair of brake pads", as such, is used in conjunction with the repair or maintenance of the entire brake mechanism of the wheel. Although there is such a service in the services as the restoration of brake pads, it is used less and less often. The market offers the widest selection of brake pads for any vehicle.

Video (click to play).

Nevertheless, some motorists do the repair of brake pads, in particular the replacement of friction linings, with their own hands. With certain skills, there is nothing difficult about it. All you need to do is have new friction linings and brake pad adhesive.

When diagnosing brake pads, it is naturally possible to visually determine that brake pad wear requires replacement. But you need to pay attention to the fact that the natural-mechanical wear of the brake pad should be uniform. If this is not the case, then it is necessary to diagnose the brake disc and both axle brakes, which means that something is wrong. Checking the working brake cylinder piston is mandatory.

It is necessary to draw your attention to the fact that do not get carried away with "saving" the working parts of the wheel brake system: repairing brake pads especially. But in order not to buy them on a monthly basis and not to change the pads due to constant uneven wear, you should pay attention to the serviceability of all the components of the mechanism and service them in a timely manner.

Serve with the right and right materials. Especially considering the fact that more and more cars are equipped with disc brakes. And disc brakes are a rather complex mechanism that operates under a constant state of intense load. Pay particular attention to the type of lubricant used for the brake pads. Rather, it will be a lubricant for the brake caliper.

Conventional Negrol greases are not suitable for disc brakes. There are special requirements for disc brake lubrication.

Special lubricants for servicing disc brake calipers can be divided into three types:

Extreme pressure high temperature pastes. They are used to process brackets, reverse metal surfaces of brake pads, on anti-squeak plates.

Lubricants for caliper parts: edges of pistons, pins, bolts, bushings, oil seals. Traditional silicone greases for rubber goods and plastic parts cannot be used here due to the high temperature requirements for grease.

Universal Caliper Grease - Suitable for all moving parts, including elastic and plastic.

Thus, drawing a conclusion from all that has been said, we can summarize: in order for the car owner to bear minimal losses during the repair of the brake system, everything must be done on time. Monitor the wear of the brake pads, monitor the wear of the brake disc and timely service the working brake mechanism of each wheel.

Repairing brake pads is certainly an important matter, because despite sayings like "brakes came up with brakes" - they prevent millions of accidents every day. Well, imagine that all the cars in the world at once lost their brakes! Horror, isn't it, it is for this reason that the state of the braking system must be excellent; in no case should it be delayed or saved on repairing the brakes.

In work brake systemOf course, everything is important, but often all the honors go not to the one who truly deserves them, I mean the brake pads. It is these miniature workers who are capable of stopping a multi-ton colossus at breakneck speed, preventing an emergency situation, and all the ensuing consequences ...

Today we will focus on troubleshooting, as well as repair of brake pads, on how to independently determine the need for restoration or replacement of these elements of the brake system.

Malfunction of brake pads, however, as well as of the entire brake system, is fraught not only with danger on the road, but also with additional costs. Increased fuel consumption as well as increased wear caliper parts.

When is it time to think about repairing the pads?

To begin with, in order to timely identify any malfunctions, it is necessary to regularly, as they say, look at all the above details, in addition, you should listen to any extraneous sounds (friction, whistle, knocking, etc.). In addition, extended stopping distances and ineffective braking are clear signs of a brake pad or brake system malfunction.

If the brake pads are knocking, there may be several reasons, for example: brake disc wear, weak springs, etc. Each of these “diseases” is “treated”, the difference is only in how much the breakdown is started, as well as on how the repair will take place - with your own hands or at a service station. For self-repair, everything is on sale, from the smallest spare parts to complete kits and repair kits for repairing brake pads.

Sometimes, by the way, the whistle is not at all a reason to believe that the pads have come to an end, new pads can whistle due to grinding in, which is quite normal, and goes away by itself after several days of operation.

The very concept of “repair of brake pads»Is usually used in conjunction with the maintenance of the entire braking system. However, the services have a service called - "restoration of brake pads", however, it is less and less popular every day, since the market offers the widest selection of various brake pads.

It is necessary to diagnose brake pads in order to visually determine pad wear, as well as the need for repair or replacement. In this case, you should pay attention to the fact that the wear of the pads must be uniform. Otherwise, a thorough diagnosis of the brake disc, as well as the axle and both brakes, is necessary. It is also necessary to check the piston of the working brake cylinder.

I want to draw your attention to the fact that it is not worth getting too carried away with "salvation", that is, restoration of the working surfaces of the brake system.However, in order to keep them in good condition and not to change them monthly due to uneven wear, you need to monitor not only their surface, but also the serviceability of all other units connected with the brake system, and service them on time.

Service must be qualified, that is, using the correct materials and fixtures. Disc brakes, despite the simple principle, are a rather complex mechanism that constantly works under enormous loads. Pay particular attention to the lubrication of the brake pads or brake calipers.

Lubricants such as "Negrol" for disc brakes are not suitable, since completely different requirements are imposed on disc brakes.

Brake grease classification

There are special lubricants designed for servicing disc brake calipers, they are conventionally divided into three types.

1. Anti-seize high-temperature pastes. These are used to process brackets, as well as the back metal surfaces of the brake pads, on anti-squeak plates.

2. Lubricants for the parts of the caliper that lubricate: pins, bolts, piston edges, bushings and oil seals. Traditional silicone greases for rubber goods and plastic parts are perfect for these purposes due to the high temperature requirements for the grease.

3. Universal grease for the caliper - intended for moving parts, including plastic and elastic.

Summing up all of the above, I want to summarize: in order to minimize losses that arise during the repair of the brake system, it is necessary to diagnose and micro-repair all minor faults on time. Prevention, as you remember, is cheaper and more effective than treatment, that's the same with repair. Regularly monitor the wear of the brake pads, check the wear of the brake discs and timely service the entire brake system of the vehicle.

The natural answer to this question: repair of brake pads is needed in case of their failure. But, not everything is so simple, especially with the car's braking system. After all, the failure of any element of the brakes, especially the failure of the brake pads or the failure of the brake disc, lead not only to the creation of prerequisites for dangerous movement.

In addition, brake system malfunctions are a blow to the car owner's pocket, since with faulty brake pads or brake discs, fuel consumption and wear of the caliper parts increase.

You should think about replacing or repairing brake pads as soon as you hear that your brake pads are whistling or knocking.

If your brake pads are knocking, there may be different reasons for this. Worn brake disc, loose springs, etc. Treatment of all these "diseases" occurs depending on the diagnosis, and you are able to fix some malfunctions with your own hands. Moreover, repair kits with a set of small parts are sold for repairing brake pads.

If, even new, brake pads whistle, then again there are several reasons for this. Lapping pads, brake disc malfunctions or a small area of contact with the disc of an unevenly worn pad.

As such, the concept of "repair of brake pads" is used in conjunction with the repair or maintenance of the entire brake mechanism of the wheel. Although there is such a service in the services as the restoration of brake pads, it is used less and less often. The market offers the widest selection of brake pads for any vehicle.

When diagnosing brake pads, you will naturally visually determine that brake pad wear requires replacement. But you need to pay attention to the fact that the natural-mechanical wear of the brake pad should be uniform. If this is not the case, then it is necessary to diagnose the brake disc and both axle brakes, which means that something is wrong. Checking the working brake cylinder piston is mandatory.

Conventional Negrol greases are not suitable for disc brakes. There are special requirements for disc brake lubrication.

Brake grease classification

Special lubricants for servicing disc brake calipers can be divided into three types.

Extreme pressure high temperature pastes. They are used to process brackets, reverse metal surfaces of a brake shoe, on anti-squeak plates.
Lubricants for caliper parts: edges of pistons, pins, bolts, bushings, oil seals. Traditional silicone greases for rubber goods and plastic parts cannot be used here due to the high temperature requirements for grease.
Universal Caliper Grease - Suitable for all moving parts, including elastic and plastic.

Good luck with timely maintenance of the brake system and, God forbid, repairing brake pads.

But in any case, we will briefly note the main thing concerning the brakes in the car. Most modern machines use disc brakes, which are controlled by a hydraulic drive. We'll tell you about drums another time - they are still quite common on inexpensive cars. Today we will focus on disc brakes and specifically on the calipers, their most complex parts.If you decide today to find out the maximum about the evolution and design of brakes, then in addition you can open in the adjacent tabs Boris Ignashin's publications on how brake discs "won" drumsand also about the most advanced braking systems of modern sports cars... In this article, there will be little theory: having understood the main thing, we will go to the workshop.So, disc brakes consist of a brake disc and a brake caliper with an integrated working brake cylinder (or several cylinders). Globally, there are two types of brake calipers: floating and fixed. In the first version, the caliper is attached to the steering knuckle directly or to a special bracket using guide pins and has a working piston (or pistons) on one side only.It turns out that when you press on the brake pedal, the force from the foot through the pedal and the hydraulic fluid is transmitted to the piston.Which, in turn, brings the inner pad to the disc, rests against it there, and now the entire caliper begins to move, and with it the outer brake pad.Nobody needed to prove the need for regenerative braking, that is, one in which the energy of the car is accumulated again, so that it can then be used for acceleration.Another thing is a fixed caliper. If you need to stop an airplane, train or Audi RS6, you cannot do without just such a brake mechanism. There are pistons in it on both sides, the caliper is rigidly fixed on the steering knuckle, and the force that develops on the pads can easily stop a two-ton car from 100 km / h at a distance of 35 meters. If we talk about the advantages of floating calipers, then this is undoubtedly cheapness and weight, as a disadvantage - they are relatively weak. Fixed calipers are the exact opposite of floating ones, everything is very expensive here, they are quite heavy, but in the fight to accelerate deceleration, they will undoubtedly be in the lead.The repair problems for both brake calipers are about the same. Due to constant contact with water, dirt and sand, the piston seals can collapse and cause the piston to jam in the caliper, with the loss of everything for which they were created and installed on the car.the friction surfaces on the guide pins wear out and can cause the caliper to skew and malfunction.Repair kits are sold, they often even contain a special heat-resistant lubricant. Small but headache.As for the brake pads, they are consumables. They are a metal plate with a friction lining glued to its surface. The pads differ mainly in the shape and area of the working surface, but the essence is the same. We will not delve into the chemical composition of the friction lining, we can only add that it can be both ceramic and carbon fiber. On all modern cars, a wear sensor is installed on one of the brake pads (on the inner one) - an ordinary spring, which, when the time comes, begins to creak terribly, contacting the brake disc.Let's pay attention to the brake discs. Usually they are made of cast iron - cheap and cheerful. And if you have, say, a Hyundai Accent and are not going to the Northern Loop, then this is more than enough. The most common problems with such discs are wear and tear. Wear, as you might guess, is due to friction. But it is not always uniform.Looking at the disc, you can often see grooves on its surface: this is also friction, but created by particles of dust and dirt, which act as an abrasive material. And if the depth of such grooves begins to exceed all permissible norms, the disc will have to be pierced, and when there is nowhere to sharpen, it will be replaced.With regard to warpage, the overheating effect is at work. When braking, the disc heats up and expands, and after the pedal is released, it cools. If the heating is not strong, and the cooling is smooth, then everything is fine. If the braking is sharp or prolonged at a high speed, and the cooling occurs quickly (for example, with water from a puddle), then the disc is most likely deformed and will not return to its original shape. If the disc is strongly warped, then when braking the car will vibrate. You can align a warped disc in the same way as in the case of grooves, if there is room for alignment.As promised, we are moving from theory to practice. Below we reviewed the process of replacing brake pads and "quick" restoration of the rear caliper to work on a Jeep Patriot.We started with the banal removal of the rear wheel. I should have said earlier, but better later than never: to loosen the bolts (as in our case) or wheel nuts, it's good when the car is still on the surface, so that later it would be easier to unscrew them. Next, unscrew the brake caliper guide bolts.By the way, if you just need to replace the pads, it is often enough to unscrew only the lower bolt and lift the caliper up. The pads were removed.The picture opened up depressing. The sealing cuff is swollen, and we do not have a repair kit.Usually, if the time is a little longer and the conditions are less "field", new seals are used, but not today - there are no shops with spare parts for Jeep within reach, but you have to go. Fortunately, the cuff, albeit hypertrophied, is intact. We need to keep it intact at all costs!Well, disconnect the brake hose from the caliper.In an amicable way, the hose must be closed with a plug so that the brake fluid does not leak out, but we are in a hurry and just pinch it: “once you can,” the specialist reassures.Just in case, we note that pinching in a bad scenario of the development of events may result in a jam of the metal "core" of the brake hose, but we did it. And we go further - we need to disassemble the sour caliper.There is no way to push in or remove the piston from the caliper. Neither the compressed air supplied to the channel in the caliper, nor the obscene language of the mechanic helped. It looks like you can't do without hydraulics ... We reconnect the caliper to the brake hose. We put one of the idle observers at the steering wheel and make it extremely careful to press the brake pedal at full speed. The brake fluid won - the piston began to squeeze out and at some point almost fell out (for the future, be careful).Disconnect the caliper and send it for inspection.Wash with soapy water. You cannot wash with petroleum products - they can get on the cuff, which will cause it to blow even more. Rust was found on the piston and on the cylinder bore in the caliper, and we need to remove it to restore it.To do this, first remove the sealing cuff, practically not breathing over it, so as not to damage it. We finally get the piston. We take a suitable tool and, just as gently, remove the piston o-ring from the recess in the caliper cylinder.The mechanic competently, armed with a "zero" (M40 sandpaper, or even with a lower number after the letter), began to remove the cause of the wedging. Some 20 minutes, and the elements of the brake mechanism look like new. We put the O-ring in place - into the cylinder. We apply a thin layer of fresh brake fluid to the piston, after which we put a cuff on it and very carefully install it into the caliper cylinder. We almost pray for the cuff and without unnecessary movements we insert it into the selection on the support. Ready!We apply special grease to the guide bolts of the caliper before installing them.The upper and lower guide bolts differ slightly from each other in that there is a bushing on the upper one, although, depending on the wishes of the designer, it can also be on the lower bolt. It is very important not to mix up the bolts when installing them. The specialist clarified that in this case, vibrations may occur on certain models during braking.While we were amazed, the mechanic installed the upper guide bolt and new brake pads, which, by the way, are also different: one, as the mechanic put it, has a "buzzer" (wear sensor), the other does not. The one with the "squeaker" is internal. We lowered the caliper into place and tightened the guide bolts. Connect a hose to the brake caliper.One of us pressed the brake pedal as best he could, the rest watched the cuff. No leak was found. Everything, you can breathe out. It remains to pump the hydraulic system in order to expel air from there, and you can go.For pumping, they put the owner, who was tired of waiting, behind the wheel, and made him work his foot on the brake pedal. At this time, an experienced specialist opened the fitting on the support. As soon as the brake fluid began to flow out without bubbles, it was closed. Fresh brake fluid was added to the expansion tank of the brake master cylinder under the hood.Now all that remains is to change the pads on the left side - here everything is in order with the caliper, so no more "dancing with a tambourine".***
The car brakes without pulling, no squeaks.The owner ticked the box that at the first opportunity it was necessary to buy repair kits and replace the piston cuffs of the rear calipers, and in the near future - also the silent blocks of the front levers. Special thanks to a specialist who, as it turned out, in his spare time is a mechanic of one of the little-known rally teams.The brakes of the front and rear wheels on VAZ 2106 cars wear out unevenly, and in most cases the front pads have to be changed much more often. But it is not worth delaying the replacement of the rear ones, since not only the quality of braking depends on this, but also the holding of the car on a slope with the help of the hand brake.The procedure for this maintenance is not very difficult to perform, but it will take about an hour to service both wheels of the car. To carry out this work, we need the following tool:

Flat and Phillips screwdriver

Pliers

Long nose pliers

Now I will try to describe in more detail all the steps that will need to be taken to complete this work. So, the first step is to remove the rear wheel brake drum.Then we will see the following picture:As you can see, the pads are fastened with springs, which we will need to remove. We pry the lower spring with a screwdriver and try to rip it down, usually we don't have to make much effort.After that, with pliers, we turn the cotter pin, which secures a small spring that holds the block in an upright position. This is shown more clearly in the photo below:Then we go to the left side of the mechanism and take out the cotter pin that secures the handbrake lever:Now go to the upper part and release the pads from the spring in this part in the same way. how it was done from the bottom side:After removing the upper spring, the pads will fall by themselves and will be completely free:We buy new brake pads, the price of which varies from 300 to 800 rubles, depending on the manufacturer, and install them in the reverse order. You can also tighten the springs with a screwdriver or long-nose pliers, it all depends on your preference, as they say, who is more comfortable.It should be borne in mind that after installing new rear brake pads on the VAZ 2106, there is a chance that it will not work to put on the brake drums. If this problem also touches you, then it will be necessary to slightly loosen the parking brake cable. Read about this in more detail in the article on adjusting the handbrake.After the drums are worn, check the effectiveness of the handbrake so that it is not too loose, and tighten it if necessary. At the first time of operation after replacement, do not brake sharply and try not to drive at high speed, as the pads must wear on until the brakes become effective.Replacing brake pads countless times has been described and shown in the video. For our part, we will not only answer the questions: how to assess the wear of the brake pads, what is the minimum thickness of the friction linings, but also show the subtleties of servicing the front and rear brakes when replacing the pads with our own hands.It would be wrong to talk about the average service life for the reason that the wear rate depends on many parameters:

the quality of the composition of the friction layer, brake discs;

operating conditions of the vehicle. Constant dynamic driving with frequent decelerations, transporting goods or operating a car in mountainous terrain can halve the time for replacing the pads;

serviceability of the braking system, correct distribution of the braking force between the wheels. Souring of the guide calipers, wedging of the pistons, incorrect adjustment of the parking brake lead to accelerated wear of the friction linings.

Remove the pads and measure the residual thickness of the friction layer with a vernier caliper.In the workshop manual, you can find the minimum thickness of the front and rear brake pads. Please note that the thickness of the friction pads is not the distance from the metal base to the edges of the pads, but the distance from the edges to the technological margin (about 3 mm). This means that if the friction linings are worn out by half of the original thickness, then this is not 50% of wear, but all 65-70%. In some designs, the remaining life of the brake pads can be estimated by the distance to the contact plate of the brake pad wear sensor.

Wait until the wear sensor is triggered. Depending on the device of the warning system, a signal for replacement will be a metal squeak or a wear indicator on the dashboard. It is first necessary to check the operability of the electronic system. Many drivers, not wanting to restore the performance of the sensors, install tricks. In this case, the error light on the wear sensors does not light up on the dashboard, and the system does not respond to critical wear. It is necessary to change the pads, in the design of which there is no wear indicator, at the moment when the plane of the working surface is equal to the bottom of the groove in the middle of the friction lining.

Replacing the front brake pads is shown in the video and described using the Daewoo Matiz as an example. Since the device and principle of operation of disc brakes on modern passenger cars are extremely similar, the instructions and video will help you replace brake pads with your own hands not only on Daewoo, but also on VAZ, Opel, Ford, Renault, Kia, etc.

Loosen the wheel bolts.

Raise the front of the vehicle from the replacement side, pre-installing the wheel chocks on the diagonally opposite side. Use the jack only for raising and lowering the car, and during the repair the body must be fixed on the stops.

Remove the wheel.

Use an enema or syringe to pump out some brake fluid from the reservoir. Since the new pads will be wider than the worn out friction linings, you will have to press in the brake cylinders to install them. Pumping down will prevent the brake fluid from spilling out of the reservoir due to a change in the volume of the brake line.

Use a slotted screwdriver to press in the piston slightly. The tip must be inserted between the working surface of the inner brake pad and the piston. Since you need a lot of pressure to press in, arm yourself with a screwdriver of sufficient length or an extension cord to create a lever.

Using a socket or box wrench 14, unscrew the bolt of the lower caliper guide.

Without unscrewing the upper bolt, throw the lower part of the caliper up and secure with wire.

Remove the front brake pads from the caliper.

Before installing new front friction pads, the guide plate and the bracket seats must be thoroughly cleaned. As shown in the video, a slotted screwdriver and a metal brush are best suited for this purpose. For free movement of the front friction linings along the guide plates, the plates themselves and the ends of the pads must be lubricated with high-temperature caliper grease.After all the manipulations, the working surface of the discs and brake pads must be free of fat deposits, residues of any lubricant.Final operations for replacing the front pads:

install the guide plates;

insert new friction linings into the grooves;

reassemble the caliper and all other elements in the reverse order to removal.

After completing the replacement, check the brake fluid level.

Disengage the end of the parking brake cable from the groove of the manual pads drive lever.
Remove the top and bottom return springs.
Unscrew the "soldiers" holding the rear friction linings.
Install the end of the parking brake cable into the groove of the manual shoe feed lever.
Place the new pad in the intended place of attachment, and then fix it with the "soldier".
Install the regulator with the lever in the grooves of the new shoe, and then attach it to the brake shield, installing the "soldier".
Install the upper and lower return springs.

In order not to look at the parts of the rear drum brakes with bewildered eyes during assembly, take a photo before disassembling that will allow you to easily assemble the brake mechanism.

If you decide to change the brake pads, but keep the old drums, it is advisable to cut down the "collar". In the case of deep potholes, uneven wear, it is advisable to grind the drums before installation. After completing work, be sure to adjust the parking brake.

The device and principle of operation of the rear disc brakes are not much different from the mechanisms on the front axle, therefore, the replacement process is extremely similar. We offer you to watch a video that shows in detail how to replace the rear brake pads on disc brakes.